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91.
Alexander A. Larin Dmitry M. Bystrov Leonid L. Fershtat Alexey A. Konnov Nina N. Makhova Konstantin A. Monogarov Dmitry B. Meerov Igor N. Melnikov Alla N. Pivkina Vitaly G. Kiselev Nikita V. Muravyev 《Molecules (Basel, Switzerland)》2020,25(24)
In the present work, we studied in detail the thermochemistry, thermal stability, mechanical sensitivity, and detonation performance for 20 nitro-, cyano-, and methyl derivatives of 1,2,5-oxadiazole-2-oxide (furoxan), along with their bis-derivatives. For all species studied, we also determined the reliable values of the gas-phase formation enthalpies using highly accurate multilevel procedures W2-F12 and/or W1-F12 in conjunction with the atomization energy approach and isodesmic reactions with the domain-based local pair natural orbital (DLPNO) modifications of the coupled-cluster techniques. Apart from this, we proposed reliable benchmark values of the formation enthalpies of furoxan and a number of its (azo)bis-derivatives. Additionally, we reported the previously unknown crystal structure of 3-cyano-4-nitrofuroxan. Among the monocyclic compounds, 3-nitro-4-cyclopropyl and dicyano derivatives of furoxan outperformed trinitrotoluene, a benchmark melt-cast explosive, exhibited decent thermal stability (decomposition temperature >200 °C) and insensitivity to mechanical stimuli while having notable volatility and low melting points. In turn, 4,4′-azobis-dicarbamoyl furoxan is proposed as a substitute of pentaerythritol tetranitrate, a benchmark brisant high explosive. Finally, the application prospects of 3,3′-azobis-dinitro furoxan, one of the most powerful energetic materials synthesized up to date, are limited due to the tremendously high mechanical sensitivity of this compound. Overall, the investigated derivatives of furoxan comprise multipurpose green energetic materials, including primary, secondary, melt-cast, low-sensitive explosives, and an energetic liquid. 相似文献
92.
Oleg Parenago Alexey Rybaltovsky Evgeniy Epifanov Andrey Shubnyi Galina Bragina Alexey Lazhko Dmitry Khmelenin Vladimir Yusupov Nikita Minaev 《Molecules (Basel, Switzerland)》2020,25(24)
To obtain a supported heterogeneous catalyst, laser ablation of metallic palladium in supercritical carbon dioxide was performed in the presence of a carrier, microparticles of γ-alumina. The influence of the ablation process conditions—including supercritical fluid density, ablation, mixing time of the mixture, and laser wavelength—on the completeness and efficiency of the deposition of palladium particles on the surface of the carrier was studied. The obtained composites were investigated by scanning and transmission electron microscopy using energy dispersive spectroscopy. We found that palladium particles were nanosized and had a narrow size distribution (2–8 nm). The synthesized composites revealed high activity as catalysts in the liquid-phase hydrogenation of diphenylacetylene. 相似文献
93.
Marcos V. Foguel Angelica M. Balcarcel Mark A. Reed Percy Calvo‐Marzal Yulia V. Gerasimova Dmitry M. Kolpashchikov Karin Y. Chumbimuni‐Torres 《Electroanalysis》2020,32(4):835-841
One major challenge in nucleic acids analysis by hybridization probes is a compromise between the probe's tight binding and sequence‐selective recognition of nucleic acid targets folded into stable secondary structures. We have been developing a four‐way junction (4WJ)‐based sensor that consists of a universal stem‐loop (USL) probe immobilized on an electrode surface and two adaptor strands (M and F). The sensor was shown to be highly selective towards single base mismatches at room temperature, able to detect multiple targets using the same USL probe, and have improved ability to detect folded nucleic acids. However, some nucleic acid targets, including natural RNA, are folded into very stable secondary and tertiary structures, which may represent a challenge even for the 4WJ sensors. This work describes a new sensor, named MVF since it uses three probe stands M, V and F, which further improves the performance of 4WJ sensors with folded targets. The MVF sensor interrogating a 16S rRNA NASBA amplicon with calculated folding energy of ?32.82 kcal/mol has demonstrated 2.5‐fold improvement in a signal‐to‐background ratio in comparison with a 4WJ sensor lacking strand V. The proposed design can be used as a general strategy in the analysis of folded nucleic acids including natural RNA. 相似文献
94.
95.
Dmitry Yu. Murzin 《Reaction Kinetics and Catalysis Letters》2007,91(1):37-43
The general form for adsorption on nanoparticles is presented. Conditions for the validity of Langmuir adsorption isotherm
for supported nanoparticles are discussed. 相似文献
96.
Natalia P. Kuzmina Dmitry M. Tsymbarenko Igor E. Korsakov Zoya A. Starikova Kostantin A. Lysenko Olga V. Boytsova Andrey V. Mironov Irina P. Malkerova Andrey S. Alikhanyan 《Polyhedron》2008
The novel mixed ligand complexes [Ca(hfa)2(diglyme)(H2O)] (I), [Sr(hfa)2(diglyme)(H2O)] (II) and [Ba(hfa)2(diglyme)2] (III) (Hhfa = 1,1,1,5,5,5-hexafluoropentane-2,4-dione, diglyme = 2,5,8-trioxanonane) were synthesized by the reactions of the alkaline earth element (AEE) carbonates in n-hexane with a mixture of Hhfa and diglyme, and they were characterized by elemental analysis, 1H and 13C NMR, and FTIR spectroscopy. The crystal structures of I–III, consisting of mononuclear isolated molecules, have been determined. The thermal behavior and composition of the vapor phase have been studied for I–III by thermal analysis at low pressure and mass spectrometry using a Knudsen cell. The stability of the mixed ligand complexes [M(hfa)2(diglyme)n] to the removal of diglyme molecules under heating decreases in the row I > II ≈ III, and only I evaporates as the mixed ligand complex after water removal. 相似文献
97.
Maria S. Tarasenko Nikolay G. Naumov Dmitry Yu. Naumov Sung-Jin Kim Vladimir E. Fedorov 《Polyhedron》2008
A series of new compounds containing rare earth cations (Eu to Yb) and paramagnetic cluster anion [Re6Te8(CN)6]3− was prepared and investigated. The X-ray structural analyses have revealed that the compounds [{Ln(H2O)4}{Re6Te8(CN)6}] · 2.5H2O; Ln = Eu (1), Tb (3), Dy (4), Ho (5), Er (6), Tm (7), [{Gd(H2O)3}{Re6Te8(CN)6}] · 2.5H2O (2) and [{Yb(H2O)4}{Re6Te8(CN)6}] (8) are three-dimensional polymers based on Re–CN–Ln interactions. Measurements of magnetic susceptibility for 2 and 5 showed that effective magnetic moment (at 300 K) was 8.13 μB for compound 2 and 10.79 μB for compound 5 with weak antiferromagnetic ordering appeared at low temperatures. 相似文献
98.
Dr. Eduard E. Karslyan Dr. Alexandra O. Borissova Prof. Dr. Dmitry S. Perekalin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(20):5676-5679
A polycyclic aromatic ligand for site-selective metal coordination was designed by using DFT calculations. The computational prediction was confirmed by experiments: 2,3,6,7-tetramethoxy-9,10-dimethylanthracene initially reacts with [(C5H5)Ru(MeCN)3]BF4 to give the kinetic product with a [(C5H5)Ru]+ fragment coordinated at the terminal ring, which is then transformed into the thermodynamic product with coordination through the central ring. These isomeric complexes have markedly different UV/Vis spectra, which was explained by analysis of the frontier orbitals. At the same time, the calculations suggest that electrostatic interactions are mainly responsible for the site selectivity of the coordination. 相似文献
99.
Dmitry V. Pasyukov Andrey Yu. Chernenko Konstantin E. Shepelenko Vadim V. Kutyrev Victor N. Khrustalev Victor M. Chernyshev 《Mendeleev Communications》2021,31(2):176-178
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100.
Dmitry A. Gruzdev Galina L. Levit Victor P. Krasnov Evgeny N. Chulakov Liliya Sh. Sadretdinova Aleksandr N. Grishakov Marina A. Ezhikova Mikhail I. Kodess Valery N. Charushin 《Tetrahedron: Asymmetry》2010,21(8):936-942
A comparative study of the kinetic resolution of racemic 2-methyl-1,2,3,4-tetrahydroquinoline and 2,3-dihydro-3-methyl-4H-1,4-benzoxazine using N-phthaloyl-(S)-amino acyl chlorides as chiral acylating agents is described. Temperature and solvent effects on the stereochemical features have been examined. It has been found that N-phthaloyl-(S)-phenylalanyl and N-phthaloyl-(S)-2-phenylglycyl chlorides bearing aromatic substituents close to the stereogenic centre are more stereoselective acylating agents than N-phthaloyl-(S)-alanyl chloride. For the preparative kinetic resolution of racemic amines N-phthaloyl-(S)-phenylalanyl chloride proved to be the most appropriate chiral acylating agent. 相似文献